Some doctors even suggested operating on the lad – until it emerged Aisling’s breast milk was causing his illness.

The pro-active mum, from Crossabeg in Wexford, took a food intolerance test and discovered a range of grub did not suit her and was allowing toxins in her milk to pass straight into Aaron’s system.

As soon as she changed her diet, her son began thriving.

Hotel chef Aisling said: “I had a tiny infant, just 12 weeks old, who screamed from the first day he was born, and vomited constantly following feeds.

“We were distraught and bewildered as to why this was happening, and we tried all sorts of different routines and attempts to soothe him. But nobody could tell us what was wrong.”

Aisling and husband Adam, who are also parents to four-year-old Julianna, were told by some doctors he would need surgery.

The fact that her sister is milk intolerant led her to think her baby was also having some sort of allergic reaction to his feed. She added: “We contacted the Fitzwilliam FoodTEST Clinic in Dublin, where my sister was tested, and a simple blood test revealed that I was intolerant to a range of common foods, mostly wheat, gluten, dairy and eggs.”

The tot, now five months old, had also bad nappy rash and skin irritation, and the fact he could not keep his feed down meant he was not developing properly.

Aisling added: “I have adjusted my diet considerably. Aaron is thriving, and I have also seen a huge improvement in my own health.

“I had bad skin, nausea, and digestion problems that have completely disappeared. Aaron may have the same issues, to some degree, and my food intolerance was causing toxins to be transferred to him via my breast milk.

“It is very upsetting to have a child that doesn’t feed properly, and cries from pain. So, while this type of issue with food intolerance and breast-feeding is very rare, it is easily solved, and something for other mums to consider if their infant is sick in this way too.”

A spokeswoman for the Dublin clinic said: “Aisling was breastfeeding Aaron, as is generally encouraged by the maternity services.

“She wanted to give her son the best possible start in life, with natural breast milk, the healthiest form of milk for babies, with its balanced nutrients and immunity boosting properties.

“Unfortunately for Aisling and Aaron, it was actually mum’s breast milk that was the cause of all Aaron’s distress, as a food intolerance test later showed.”

The Fitzwilliam FoodTEST can be ordered by post and carried out at home to be returned for lab analysis. Results can be delivered in person, or by post, with advice on eliminating, or substituting for, problematic foodstuffs.